1. Field of the Invention
The invention relates to ostomy devices which are constructed in two parts.
2. Description of the Related Art
Ostomy devices in two parts comprise a fixing or support device which is adhesively-bonded to the skin around an ostomy, and a removable pouch which is intended to be connected to the fixing device. The advantage of these two-part devices is that a single adhesive-bonding of a fixing device around the ostomy allows the successive use of a plurality of pouches, generally at least three. Although it is possible to produce materials which constitute gums which are capable of absorbing humidity and which are non-allergenic, the detaching operation still subjects the skin to stresses which it is desirable to spread over time.
Various connections have therefore been produced which are intended to fix a collection pouch in a fluid-tight manner to a fixing device. There are substantially two generic types of such connection, a mechanical type and an adhesive type.
There are a number of variants of the connections of the mechanical type. Three are described which are representative of this range.
In a first example of a mechanical connection, a fixing device having a gum disc carries a ring having a plurality of lips which delimit a channel in which a wall of a ring carried by a pouch is accommodated. The mechanical strength is provided by co-operation of lips of the two rings, the sealing is provided by the contact of a lip of the ring with the body of the ring, and the guiding for the positioning is provided when a ring is accommodated on the other ring, the engagement being provided simply by applying a force to the rings.
A second known mechanical connection device is such that a fixing device and a pouch each comprise a ring, the rings having lips which are intended to fit into each other in order to provide both the mechanical strength and sealing.
A third known mechanical connection has a small pivoting lever which rotates a blocking device which, after two rings are engaged one on the other, blocks them by means of locking in order to provide a very high level of strength.
All these known mechanical devices have the advantage of allowing the co-operation of two rings only when they are correctly centred one on the other, with the result that the positioning of the two connection portions is excellent.
However, they do have disadvantages. The sealing is obtained by means of contact of one or more lips with a complementary surface. In order for a lip to provide a good level of sealing, it must have a good level of resilience, that is to say, it must either be very thin or be formed from a relatively flexible material. If the material of the ring, and therefore the lip, is flexible, the mechanical strength obtained is reduced. If the material of the ring is rigid and hard, the connection as a whole constitutes a rigid element which brings about a degree of discomfort.
Furthermore, all the elements having lips must comply with strict tolerances; they are formed by means of injection and are therefore costly.
Given the disadvantages of these mechanical connections, attempts have been made to use connections which function by means of adhesive-bonding. Connections have therefore been produced in which an adhesive disc, which is fixedly joined to the pouch and which is protected by a protective paper, is adhesively-bonded to a strip of a device for fixing to the user. The advantages of such a connection by means of adhesive-bonding are clear: the assembly can be flexible and thin, and can therefore provide a high level of comfort and, as the adhesive-bonding surface can be extensive, an excellent level of sealing and mechanical strength can be provided.
However, this connection by means of adhesive-bonding presents a problem: it is difficult to position an adhesive portion of the pouch on the fixing device whilst ensuring the alignment of the holes of these two elements.
Given the very adhesive nature of the connection portion of the pouch, as soon as it has begun to adhesively-bond to an opposing portion, it is no longer possible to displace the two portions relative to each other. Furthermore, if the two connection portions are flexible, and therefore provide an advantage in terms of comfort, the uniform application of the two portions one to the other presents problems owing to this very flexibility.
According to document FR-2 396 541, an ostomy pouch connection is already known such that a fixing device comprises a circular end-piece which extends from the device around the hole thereof and which is surrounded by an adhesive-bonding strip and, at the outer side thereof, hook and loop type fixing elements. The pouch has a connection portion which comprises a circular adhesive surface which surrounds a hole and, around this adhesive surface, hook and loop type fixing elements. When it is used, the end-piece of the fixing device is introduced into the hole of the pouch before the adhesive surface comes into contact with the adhesive strip or the hook and loop type fixing elements move into co-operation. The holes are therefore well aligned. A first disadvantage of this device is that the end-piece, in order to be effective, must have a specific length: it confers a high level of rigidity on the fixing portion and therefore brings a considerable level of discomfort. In particular, as the adhesive surface surrounds the end-piece, the paper which protects it must be removed before the end-piece moves into the hole of the pouch. The end of the end-piece is therefore necessarily in contact with the exposed adhesive surface before being introduced into the hole of the pouch. If the adhesive is very effective, it is almost impossible to detach it without significantly damaging the adhesive: this is without doubt the reason why the function of mechanical strength of the pouch is not provided by the adhesive surface, but instead by the hook and loop type fixing elements.